It's plain I repair clumsily (7)
I believe the answer is:
prairie
'it's plain' is the definition.
(type of plain)
'i repair clumsily' is the wordplay.
'clumsily' indicates an anagram.
'i'+'repair'='irepair'
'irepair' is an anagram of 'PRAIRIE'.
(Other definitions for prairie that I've seen before include "Large open area of grassland in the US" , "Barren plain" , "Continental grassland of N America" , "Large tract of grassland in N America" , "Cowboy song: ` `Bury me not on the lone .......' '" .)